It might seem surprising today in the era of Donald Trump, but Republicans in the United States once championed immigration and supported pathways to citizenship for undocumented Americans.

In January 1989, Ronald Reagan’s final speech as president was an impassioned ode to the immigrants who made America “a nation forever young, forever bursting with energy and new ideas”.

Contrast this with Trump, who has normalised dehumanising rhetoric and policies against immigrants. In this year’s presidential campaign, for instance, he has referred to undocumented immigrants as “animals” who are “poisoning the blood of our country”.

Both Trump and his vice presidential running mate, JD Vance, also repeated a false story about Haitian “illegal aliens” eating pets in Springfield, Ohio.

Perhaps most troubling, Trump has pledged to launch “the largest deportation operation in the history of our country”, if he’s elected.

Nativism, or anti-immigrant sentiment, has a long history in American politics.

In 1924, a highly restrictive immigration quota system based on racial and national origins was introduced. This law envisaged America as a white, Anglo-Saxon, Protestant nation.

However, there was no restriction on immigrants from the Western Hemisphere. The agricultural and railroad sectors relied heavily on workers from Mexico.

In 1965, the quota system was replaced by visa preference categories for family and employment-based migrants, along with refugee and asylum slots.

Then, as violence and economic instability spread across Central America in the 1970s, there was a surge in undocumented immigration to the US.

Scholar Leo Chavez argues that in the late 1980s and early 1990s, an alarmist “Latino threat narrative” became the dominant motif in media discussions of immigration.

This narrative was frequently driven by Republican politicians in states on the US-Mexico border, who derived electoral advantage from........

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